Academic Computing & Media Services

SFTP - Secure File Transfer Protocol

'Sftp' is a secure version of the File Transfer Protocol (ftp). It uses FTP commands to transfer files securely between accounts, whether the accounts are on the same machine or on different machines, including your home computer, if it is properly configured.

This article is composed of the following sections:

• Basic Instructions
• List of SFTP Commands

Basic Instructions

To transfer a file you must know the machine name (e.g. mi5.ucsd.edu), and the name and password of the account with which you want to copy files.

Getting started with sftp:

Let's say you were on your account "jbond" and you wanted to transfer a file to an account drno on mi5.ucsd.edu. First, you should start sftp and tell it to which username and machine you want to hook up:

	% sftp drno@mi5.ucsd.edu
	

If this is the first time you have connected to the remote machine, mi5.ucsd.edu, a security warning message will be displayed:

	Connecting to mi5.ucsd.edu...
	The authenticity of host 'mi5.ucsd.edu (127.0.0.1)' can't be established.
	RSA key fingerprint is e4:16:3a:3f:69:b6:37:69:69:ca:bb:a6:33:fa:47:ac.
	Are you sure you want to continue connecting (yes/no)?
	

Type 'yes', and hit return. The remote machine will warn you that it now regards mi5.ucsd.edu as authentic, and then asks you for drno's password.

	Warning: Permanently added 'mi5.ucsd.edu' (RSA) to the list of known hosts.
	drno@mi5.ucsd.edu's password: 
	

If the account and password are correct, then the sftp prompt ( sftp> ) will appear:

	sftp>
	

To copy a file from the remote account to your original acount, use the "get" command followed by the name of the file you want to copy:

	sftp> get martini.txt
	

To copy a file from your original account into the remote account, use the "put" command followed by the name of the file you want to copy:

	sftp> put shaken-not-stirred.txt

	

You are initially logged into the home directory of the remote account. It is possible to change to a different directory on the remote account using the "cd" command, just like in Unix:

	sftp> cd mydirectory
	

The "ls" command may be used to list the contents of the current directory on the remote machine.

	sftp> ls

	

Alternatively, "ls -l" can be used to obtain a more detailed listing, showing the file's access privilages, size, and the date it was last modified.

A list of sftp commands is available within ftp by typing the word "help" or a question mark (?) at the prompt:

	sftp> help
	

To exit the ftp program, type the command "quit" at the ftp prompt.

	sftp> quit
	%
	

To copy multiple files, use wildcard characters to specify many files. A 'wildcard' character is a punctation mark that represents any character, or any number of any characters. An asterisk '*' represents any number of any characters, and a question mark '?' represents one of any character.

	sftp> get *
	

For more information on sftp, see the manual page for sftp:

	% man sftp
	

List of SFTP Commands

While the version of SFTP that you are using will vary from machine to machine, here are some of the common commands, along with a brief definition

Commands:
cd path C	hange remote directory to 'path'
lcd path	Change local directory to 'path'
chgrp grp path	Change group of file 'path' to 'grp'
chmod mode path	Change permissions of file 'path' to 'mode'
chown own path	Change owner of file 'path' to 'own'
help	Display this help text
get remote-path [local-path]	Download file
lls [ls-options [path]]	Display local directory listing
ln oldpath newpath	Symlink remote file
lmkdir path	Create local directory
lpwd	Print local working directory
ls [path]	Display remote directory listing
lumask umask	Set local umask to 'umask'
mkdir path	Create remote directory
put local-path [remote-path]	Upload file
pwd	Display remote working directory
exit	Quit sftp
quit	Quit sftp
rename oldpath newpath	Rename remote file
rmdir path	Remove remote directory
rm path	Delete remote file
symlink oldpath newpath	Symlink remote file
version	Show SFTP version
!command	Execute 'command' in local shell
!	Escape to local shell
?	Synonym for help

By zz1js 23/06/99

Revised by zz1mf 29/08/03